To respond to the HIV epidemic and reduce health disparities in HIV incidence and outcomes, we propose a Prevention Research Center (PRC) at the University of California, San Francisco (UCSF) that facilitates significant and innovative health science research through partnerships with public health colleagues that ultimately improves public health. The HIV epidemic continues to be a major public health crisis in the U.S., with more than 1 million people living with HIV and more than 50,000 becoming newly infected every year1. Given the progress in preventing and treating HIV, the Centers for Disease Control and Prevention (CDC) has identified HIV as a winnable battle, Healthy People 2020 has included HIV as a topic area, sexual health is part of the National Prevention Strategy, and the White House has made HIV a policy priority with the release of the National HIV/AIDS Strategy. HIV has had a disproportionate impact on African Americans, representing one of the largest health disparities in the U.S. While comprising just 13% of the total national population, African Americans account for 51% of all new HIV/AIDS diagnoses. While HIV disproportionately impacts African Americans, Black gay and other men who have sex with men (BMSM) are particularly impacted. In particular young BMSM (aged 13 - 24 years) are the only subpopulation where the rate of new infections continues to increase. These national data highlight the urgent need to focus research on eliminating HIV health disparities among African Americans in general and BMSM in particular. This application proposes to develop and implement authentic community engagement and support implementation of a research project that focuses on linking, engaging and reengaging in care young BMSM living with HIV. Our overall aims are to: 1. Establish a Prevention Research Center that focuses on appropriate adaptation, dissemination and implementation of HIV health disparities research for application to policy, programs and practices; 2. Enhance collaborations with partners in the community, health care systems, government agencies, institutions and universities to facilitate innovative, high-impact, multidisciplinary HIV research and knowledge translation to training, programs, practices and policies; 3. Increase the capacity of partners in the community, health care systems, government agencies, institutions and universities to understand and implement the findings from HIV research through targeted training, communication and dissemination; and 4. Develop an implementation research portfolio that translates and adapts an evidence-based intervention into practice settings. We propose to begin this portfolio by studying the implementation of an evaluated intervention to improve linkage of HIV-infected young Black MSM to clinical care.